There is known a vehicle rear body structure in which a front buckling reference hole and a bending bead are formed on the front side of each of left and right rear frames with respect to a vehicle body, and a rear buckling reference hole and a bending bead are formed on the rear side thereof with respect to the vehicle body. The bending bead on the vehicle body front side is formed inside the front buckling reference hole in a vehicle widthwise direction. In addition, the bending bead on the vehicle body rear side is formed outside the rear buckling reference hole in the vehicle widthwise direction (see Japanese Patent Application Publication No. 2013-233898, for example).
According to this vehicle rear body structure, the bending bead on the vehicle body front side and the bending bead on the vehicle body rear side are formed in a staggered pattern in the vehicle widthwise direction. This enables the rear frame to be bent in a horizontal direction by an impact load input to a rear bumper beam and thus to absorb the impact load input to the rear bumper beam.
Here, some automobiles have a gasoline tank, an intelligent power unit (IPU), and the like arranged between left and right rear frames. An IPU is an in-vehicle inverter used in hybrid electric vehicles (HEVs) and configured to improve fuel consumption and reduce exhaust gas emissions.
It is conceivable in such automobiles that, when each rear frame is bent in the horizontal direction by an impact load input to a rear bumper beam, the rear frame thus bent may come into contact with the gasoline tank, the IPU, and the like. For this reason, in order to prevent them from being damaged by such a contact, their installation locations are limited.
In addition, to prevent the bent rear frame from coming into contact with the gasoline tank, the IPU, and the like might become a hindrance in reserving a certain amount of deformation of the rear frame.